I am a Polymer Clay Artist. The examples are polymer clay and the description of techniques are common terms used in working with polymer clay.

The silicon
texture sheets do not need a release agent when used with polymer clay. The soft edges are wonderful for impressing smaller areas or working repeats.

This is made from a open weave bamboo basket. The over-under weave is very distinct. Notice the detail, it is hard to believe this is just polymer clay pressed into a texture sheet with some brown paint.

Well to be more accurate, this is ivory colored polymer clay, with a burnt umber patina.

This
texture sheet 'mica shifts' wonderfully. The image on the left is of a flat piece of clay the sense of depth is all an illusion.

Notice how it maintains the over-under pattern. Amazing!

Here
is a mokume gane sheet on a bracelet in pearl blue and greens.

If you would like more information on the technique, here is a great tutorial on the web site Polymer Clay Central: